1. Field of the Invention
The present invention relates to a cartridge case for a magnetic tape cartridge and a magnetic tape cartridge comprising a cartridge case and a tape reel contained in the cartridge case and, more particularly, to a magnetic tape cartridge case having a tape reel chamber for receiving a tape reel therein and a retainer for retaining a flexible sheet-formed memory tag out of the tape reel chamber and a magnetic tape cartridge comprising a cartridge case, a tape reel with a magnetic tape wound around and a flexible sheet-formed memory tag.
2. Description of Related Art
Typically, magnetic tape cartridges are widely used as a recording device of an external memory equipment of a computer. Such a magnetic tape cartridge comprises a single tape reel with a magnetic tape wound thereon and a cartridge case for receiving and supporting the tape reel for rotation therein. As magnetic tapes are used as a recording medium for storing an important piece of information such as computer data, the magnetic tape cartridge is made up so as to keep a magnetic tape out of troubles such as jamming and prevent it from being accidentally driven out of the cartridge case. Further, the magnetic tape cartridge is provided with an in-cartridge memory device which contains information such as the manufacturing data, the contents and the like of the magnetic tape cartridge. The in-cartridge memory device is provided with a semiconductor memory chip which enables recording and reading information about the magnetic tape itself and information recorded on the magnetic tape in a non-contact manner such as electromagnetic induction. Therefore, the in-cartridge memory device facilitates quick identification of the information contained in the magnetic tape cartridge without directly playing back the magnetic tape in the magnetic tape cartridge.
The in-cartridge memory device is installed in the cartridge case out of the way of rotation of the tape reel and is retained at a given angle in the cartridge case so as to enable a read-write device of an external memory equipment to record and read information on the in-cartridge memory device in a non-contact manner without troubles. A memory device retailer for retaining an in-cartridge memory device in position at a given angle with respect to the read-write device of an external memory equipment in a magnetic tape cartridge has been known in various forms. The memory device retainer comprises support members which are provided in two parts in two mating case sections, respectively, so as to retain the memory device tightly.
One of the memory device retainers that is incorporated in a data storage cartridge disclosed in U.S. Pat. No. 6,299,088 comprises a rear-positioning member having an angled surface formed in one of first and second case sections of a cartridge case for supporting a memory chip in position and a retaining post formed in the other case section for positioning the memory chip in position on the rear-positioning member. Another memory device retainer that is disclosed in Japanese Unexamined Patent Publication No. 2006-65924 comprises a pair of supporting braces formed in a lower case for supporting one of opposite surfaces of a memory board at a given angle thereon and a pair of holding plates formed in an upper case for holding down the memory board supported at the given angle against the supporting braces when the memory board tends to accidentally rise up due to vibrations of the under case.
Further, Japanese Unexamined Patent Publication No. 2005-322412 discloses one of general magnetic tape cartridges which is provided with an elastic member engaged with an antirotation gear for arresting a tape reel in order to prevent a magnetic tape from jamming due to accidental rotations of the tape reel during nonuse of such a magnetic tape cartridge. When temporarily coupling the first and second or upper and lower case sections to a magnetic tape cartridge before permanently fixing the first and second case sections together, the elastic member in the cartridge case forces the first and the second case section through the tap reel and, in consequence, possibly causes separation of the first and second e case section from each other. In this event, it is feared that the memory device gets out of the cartridge case through a clearance gap formed due to separation between the first and second case sections depending on circumstances. If the memory device is held out of position by the retaining structure in the cartridge case even though remaining within the cartridge case, even granting that the memory device encounters no defective recording at the earliest use of the magnetic tape cartridge, it is not improbable that the memory device encounters defective recording resulting from the progress of deterioration of a surface protective layer of the memory device due to damages by the retaining structure.
In the data storage cartridge disclosed in U.S. Pat. No. 6,299,088, which is of LTO type, a housing is assembled by connecting the first section and the second case sections together by setscrews inserted into bores of cylindrical posts provided on the first case section and tightened in openings of cylinders provided on the second case section. According to this structure, in order to assemble the data storage cartridge, it is essentially inevitable to flip or turn the data storage cartridge upside down in position after a memory chip installation stage where the second case section is put on top of the first case section and temporarily coupled together in order to be prepared to a cartridge case fixing stage where the first case section and the second case section are secured together with setscrews. In the case where the data storage cartridge is flipped upside down in position as just described above between the memory chip installation stage and the cartridge case fixing stage, the temporarily coupled first and second case sections enhances the possibility that a clearance gap is formed due to separation between the first and second case sections. In order to prevent a formation of a clearance gap between the first and second case sections, it is conceivable to hold the temporarily coupled first and second case sections firmly tight so as thereby to prevent the first and second case sections from producing a clearance gap while turning the data storage cartridge upside down in position. However, it is feared that the first and second case sections are undesirably damaged due to external force applied thereto.
Therefore, in the existing circumstances, there is a strong demand for a magnetic tape cartridge case comprising two case sections and a magnetic tape cartridge in which an in-cartridge memory hip retained by retaining means provided partly in one case section and partly in the other case section is prevented from getting out of the magnetic tape cartridge case or appropriately retained in position even when the two case sections are separated apart.